The earliest lubrication systems for conveyors were oilers manually serving wear points in conveyor machinery. As labor expense increased along with trolley complexity, there was an interest in providing lubrication stations, each carrying its own separate lubrication reservoir as seen, for example, in U.S. Pat. No. 3,903,994 to Henry F. Hafner and in U.S. Pat. No. 3,017,955 to Celso Tassile. Service of lubricant from a central reservoir remote from the point of use is exemplified in the prior art by the U.S. Pat. No. 3,785,456 to Nathan M. McIntire and Zelma M. Porter and in the U.S. Pat. No. 3,934,600 of William C. Murphy with recirculation at the lubricating valves.
The present invention goes beyond the prior art in providing more accurate chain and trolley lubrication, by providing capillary lubricant distribution under rigid quantum control and in the combination of a section of track, the track providing locating means and mounting means and lubricant heads including solenoids, valves and controls and capillaries served from a remote source of lubricant piped to the lubricating head.
The present invention provides a central lubrication supply maintained and serving all lubrication points at a fixed or constant pressure. The lubrication points are each serviced by capillary tubes with discharge ends adjusted to precision delivery to bearing or journal surfaces.
The present invention locates a solenoid operated valve in the line at the capillaries and the solenoids are fired by capacitor discharge and the interval of delivery may thus be adjusted. This type of firing of the solenoids results in accurate metering and in consequent avoidance of excess application of lubricant.
The electrical signal for discharge is via limit switches located to precision trip the capacitor discharge to the solenoid valve to cause lubricant flow in accord with track or trolley movement and position.
The position of the moving chain and trolley is made to be precise by a track section serving as the lubrication station and which is ramped to assure horizontal and vertical adjustment or alignment through the station. The track section provides a mounting base for electrical controls, limit switches, valves and capillaries and including web protected capillary access between pairs of trolley wheels, for example. This allows hitherto inaccessible points to be reached by the capillary tubes.
The electrical circuit is simple and adjustable by insertion of resistance to achieve a selected timed interval for lubricant delivery by attenuation of the capacitor discharge which fires the solenoids serving the valves. This selected delivery permeates the following objects.
Accordingly, the principal object is a new and improved lubrication system having a central lubricant supply line serving a plurality of lubrication stations. Another object of the present invention is to provide a structure or lubricating head at each lubrication station to precision locate the moving points requiring lubrication.
Another object is to synchronize the location of moving elements in proximity to capillary inboard service between trolley wheels and to outboard service of trolley wheels, for example, and to provide structural support for controls accommodating the existing conveyor or track and hence non-disruptive in installation of conveyor or apparatus.
Other objects including simplicity and ease of service and avoidance of splash and drip of lubricants will be better appreciated as the description proceeds.